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| author | Jethro Beekman <jethro@fortanix.com> | 2020-02-10 21:00:22 +0100 |
|---|---|---|
| committer | Jethro Beekman <jethro@fortanix.com> | 2020-02-10 21:00:22 +0100 |
| commit | 71b9ed4a36748be01826063951310a2da2717a9b (patch) | |
| tree | 09ac4fd1393603e4dfffa8e733085e85e07f9da9 /src/libstd | |
| parent | 236ab6e6d631f073a8c3c7439af6b2ec58ce1f25 (diff) | |
| download | rust-71b9ed4a36748be01826063951310a2da2717a9b.tar.gz rust-71b9ed4a36748be01826063951310a2da2717a9b.zip | |
Avoid jumping to Rust code with user %rsp (reentry_panic)
Diffstat (limited to 'src/libstd')
| -rw-r--r-- | src/libstd/sys/sgx/abi/entry.S | 13 |
1 files changed, 6 insertions, 7 deletions
diff --git a/src/libstd/sys/sgx/abi/entry.S b/src/libstd/sys/sgx/abi/entry.S index a08caec3c2b..ed4db287229 100644 --- a/src/libstd/sys/sgx/abi/entry.S +++ b/src/libstd/sys/sgx/abi/entry.S @@ -144,13 +144,15 @@ elf_entry: /* This code needs to be called *after* the enclave stack has been setup. */ /* There are 3 places where this needs to happen, so this is put in a macro. */ -.macro sanitize_rflags +.macro entry_sanitize_final /* Sanitize rflags received from user */ /* - DF flag: x86-64 ABI requires DF to be unset at function entry/exit */ /* - AC flag: AEX on misaligned memory accesses leaks side channel info */ pushfq andq $~0x40400, (%rsp) popfq + bt $0,.Laborted(%rip) + jc .Lreentry_panic .endm .text @@ -174,9 +176,6 @@ sgx_entry: jz .Lskip_debug_init mov %r10,%gs:tcsls_debug_panic_buf_ptr .Lskip_debug_init: -/* check for abort */ - bt $0,.Laborted(%rip) - jc .Lreentry_panic /* check if returning from usercall */ mov %gs:tcsls_last_rsp,%r11 test %r11,%r11 @@ -194,7 +193,7 @@ sgx_entry: lea IMAGE_BASE(%rip),%rax add %rax,%rsp mov %rsp,%gs:tcsls_tos - sanitize_rflags + entry_sanitize_final /* call tcs_init */ /* store caller-saved registers in callee-saved registers */ mov %rdi,%rbx @@ -212,7 +211,7 @@ sgx_entry: mov %r15,%r9 jmp .Lafter_init .Lskip_init: - sanitize_rflags + entry_sanitize_final .Lafter_init: /* call into main entry point */ load_tcsls_flag_secondary_bool cx /* RCX = entry() argument: secondary: bool */ @@ -311,10 +310,10 @@ usercall: movq $0,%gs:tcsls_last_rsp /* restore callee-saved state, cf. "save" above */ mov %r11,%rsp - sanitize_rflags ldmxcsr (%rsp) fldcw 4(%rsp) add $8, %rsp + entry_sanitize_final pop %rbx pop %rbp pop %r12 |